Question 14.75

14.75 Planning another organic foods study.

Suppose that you are planning a new organic foods study using the same moral outcome variable as described in Exercise 14.51 (page 752). Your study will randomly choose shoppers from a large local grocery store.

  1. Explain how you would select the shoppers to participate in your study.
  2. Use the data from Exercise 14.51 (page 752) to perform power calculations to determine sample sizes for your study.
  3. Write a report that could be understood by someone with limited background in statistics and that describes your proposed study and why you think it is likely that you will obtain interesting results.

14.75

(a) Answers will vary.

DFG DFE F* Power
10 2 27 3.35 0.621
15 2 42 3.22 0.821
20 2 57 3.16 0.924
25 2 72 3.12 0.97
30 2 87 3.10 0.989

(b) For , the power is already 0.924. (c) Answers will vary.